She was also unable to raise an initial £100,000 needed to prevent the sale by the end of Monday, which was the actual deadline.

On Tuesday, Robin Barton from the Bankrobber gallery in London, said "pressure is growing on the owners" to accept a seven-figure deal from an American.

The artwork in Hewlett Road has attracted hordes of visitors since it appeared on 13 April

A fundraising campaign is underway to keep the streetart where it was painted

Now the borough council has stepped in to stop work on the Grade II listed building to allow "discussions to take place about the next steps".

Mark Nelson, the council's built environment enforcement manager, said: "The temporary stop notice has been served because the council considers that works have taken place, without obtaining consent.

"It is worth clarifying that whilst the council is supportive of the public's desire to keep the artwork on this property, the temporary stop notice has been issued to protect the integrity of this listed building."

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.